API NOT found error IoT Central Rest API

Question

I get below error:-

Not Found({"error":{"code":"NotFound","message":"API not found. If you contact support, please include the following information. Request ID: 8srjji57, Time: Thu, 04 Jun 2020 04:32:05 GMT.","requestId":"8srjji57","time":"Thu, 04 Jun 2020 04:32:05 GMT"}})

The api im using is below

az rest --method get --uri https://$APP_NAME.azureiotcentral.com/api/preview/applications --headers Authorization=$API_TOKEN

The document Im following is below

https://learn.microsoft.com/en-in/learn/modules/manage-iot-central-apps-with-rest-api/3-exercise-authorize-api

Answer 1

No, and no one from Microsoft helped either.